Display device

ABSTRACT

A display device includes: a substrate including a curved portion and a flat portion; an insulating layer disposed on the substrate; a first organic light emitting diode disposed on the insulating layer and having a first projection; and a second organic light emitting diode having a second projection, wherein a light emission portion is disposed in the curved portion and the flat portion, the first projection overlaps the light emission portion disposed in the curved portion and is asymmetric in the light emission portion, and the second projection overlaps the light emission portion in the flat portion and is symmetric in the light emission portion.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. § 119 to Korean PatentApplication No. 10-2016-0118363 filed in the Korean IntellectualProperty Office on Sep. 13, 2016, the disclosure of which isincorporated by reference herein in its entirety.

(a) Technical Field

The present invention relates to a display device.

(b) Description of the Related Art

An organic light emitting diode (OLED) display displays an image byusing light that is emitted from a plurality of OLEDs. In a pixel areaon a substrate of the OLED display, there is a provided an OLED and apixel circuit.

When the OLED display uses a polymer film as a substrate, the OLEDdisplay may be flexible. Such a flexible OLED display may include acurved portion and a flat portion. For example, the curved portion maybe connected to at least one edge of the flat portion.

When the OLED emits white light, a white characteristic of lightobserved from the front thereof is different from that of light observedfrom the side thereof. This may be referred to as white angle difference(WAD). WAD serves as a factor for evaluating a variation of the whitecharacteristic at certain viewing angles. For example, WAD is determinedby measuring and evaluating levels of luminance variations and colorcoordinate variations at certain viewing angles and comparing them withthose perpendicular to the front of the screen.

Users generally watch screens at the center and in front thereof.Accordingly, when the curved portion is located at an edge of the flatportion, users see light emitted from the flat portion toward the frontof the screen and light emitted from the curved portion emitted towardthe side of the screen. In this case, the light emitted from the curvedportion has a different white characteristic from the light emitted fromthe flat portion, thereby resulting in a difference in color quality. Inother words, the color quality of light emitted from the curved portionobserved from a central and frontal region of the screen is less thanthat of light emitted the flat portion.

SUMMARY

A display device according to an exemplary embodiment of the presentinvention includes: a substrate including a curved portion and a flatportion; an insulating layer disposed on the substrate; a first organiclight emitting diode disposed on the insulating layer and having a firstprojection; and a second organic light emitting diode having a secondprojection, wherein a light emission portion is formed in the curvedportion and the flat portion, the first projection overlaps the lightemission portion in the curved portion and is asymmetric in the lightemission portion, and the second projection overlaps the light emissionportion in the flat portion and is symmetric in the light emissionportion.

The display device may further include a wiring layer disposed betweenthe substrate and the insulating layer and disposed in the curvedportion and the flat portion, wherein the wiring layer disposed in thecurved portion may overlap the first projection, and the wiring layerdisposed in the flat portion may overlap the second projection.

The light emission portion disposed in the curved portion may include afirst light emission portion corresponding to a red pixel, a secondlight emission portion corresponding to a green pixel, and a third lightemission portion corresponding to a blue pixel, and the first projectionmay overlap the first light emission portion and the third lightemission portion and may be asymmetric in the first light emissionportion and the third light emission portion.

The first projection may overlap the second light emission portion, andmay be asymmetric in the second light emission portion.

The light emission portion disposed in the curved portion may include afirst light emission portion corresponding to a red pixel, a secondlight emission portion corresponding to a green pixel, and a third lightemission portion corresponding to a blue pixel, and the first projectionmay overlap the first light emission portion and the third lightemission portion, may be asymmetrically disposed in one of the firstlight emission portion and the third light emission portion, and may besymmetrically disposed in the other of the first light emission portionand the third light emission portion.

The wiring layer may include a data line and a driving voltage line, anda space between the data line and the driving voltage line in the firstlight emission portion may be different from a space between the dataline and the driving voltage line in the third light emission portion.

The wiring layer may include a data line and a driving voltage line, aspace between the data line and the driving voltage line in the firstlight emission portion may be the same as a space between the data lineand the driving voltage line in the third light emission portion, andthe first light emission portion and the third light emission portionmay deviate from each other with respect to a vertical axis.

The light emission portion disposed in the curved portion may include afirst light emission portion corresponding to a red pixel, a secondlight emission portion corresponding to a green pixel, and a third lightemission portion corresponding to a blue pixel, the first projection mayoverlap the first light emission portion, the second light emissionportion, and the third light emission portion, the first projection maybe symmetrically disposed in the first light emission portion and thethird light emission portion, and the first projection may beasymmetrically disposed in the second light emission portion.

The insulating layer may be in contact with an upper surface of thewiring layer.

The thickness of the insulating layer may be 15,000 angstroms or less.

The first projection may be biased in a direction moving away from theflat portion toward the curved portion.

A display device according to an exemplary embodiment of the presentinvention includes: a substrate including a curved portion and a flatportion; an insulating layer disposed on the substrate; and an organiclight emitting diode disposed on the insulating layer in the curvedportion and having a projection, wherein a light emission portion isdisposed in the curved portion, the projection overlapping the lightemission portion is asymmetrically disposed in the light emissionportion, and the projection in the light emission portion is biased in adirection moving away from the flat portion toward the curved portion.

The display device may further include a wiring layer disposed betweenthe substrate and the insulating layer and disposed in the curvedportion, wherein the wiring layer overlaps the projection.

The light emission portion may include a first light emission portioncorresponding to a red pixel, a second light emission portioncorresponding to a green pixel, and a third light emission portioncorresponding to a blue pixel, the wiring layer may include a firstwiring layer overlapping the first light emission portion and the thirdlight emission portion and a second wiring layer overlapping the secondlight emission portion, and the first wiring layer may overlap the firstlight emission portion and the third light emission portion and may beasymmetrically disposed in the first light emission portion and thethird light emission portion.

The second wiring layer may be asymmetrically disposed in the secondlight emission portion.

The light emission portion may include a first light emission portioncorresponding to a red pixel, a second light emission portioncorresponding to a green pixel, and a third light emission portioncorresponding to a blue pixel, the wiring layer may overlap the firstlight emission portion and the third light emission portion, the wiringlayer may be asymmetrically disposed in one of the first light emissionportion and the third light emission portion, and the wiring layer maybe symmetrically disposed in the other of the first light emissionportion and the third light emission portion.

The wiring layer may include a data line and a driving voltage line, anda space between the data line and the driving voltage line in the firstlight emission portion may be different from a space between the dataline and the driving voltage line in the third light emission portion.

The wiring layer may include a data line and a driving voltage line, aspace between the data line and the driving voltage line in the firstlight emission portion may be the same as a space between the data lineand the driving voltage line in the third light emission portion, andthe first light emission portion and the third light emission portionmay deviate from each other with respect to a vertical axis.

The light emission portion may include a first light emission portioncorresponding to a red pixel, a second light emission portioncorresponding to a green pixel, and a third light emission portioncorresponding to a blue pixel, the projection may overlap the firstlight emission portion, the second light emission portion, and the thirdlight emission portion, the projection may be disposed to be symmetricin the first light emission portion and the third light emissionportion, and the projection may be asymmetrically disposed in the secondlight emission portion.

The light emission portion may include a first light emission portioncorresponding to a red pixel, a second light emission portioncorresponding to a green pixel, and a third light emission portioncorresponding to a blue pixel, and the second light emission portion maybe smaller than the first light emission portion and the third lightemission portion.

According to an exemplary embodiment of the present invention there isprovided a display device including: a substrate including a curvedportion and a flat portion; an insulating layer disposed on thesubstrate; a pixel electrode disposed on the insulating layer and havinga first projection and a second projection; and a wiring layer disposedbetween the substrate and the insulating layer and overlapped with thefirst and second projections, wherein one of the first and secondprojections is biased in a direction that moves away from a center of alight emission portion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view schematically showing an organic lightemitting diode (OLED) display in accordance with an exemplary embodimentof the present invention.

FIG. 2 is a cross-sectional view of the OLED display shown in FIG. 1according to an exemplary embodiment of the present invention.

FIG. 3 is a layout view schematically showing a plurality of pixels ofan OLED display according to an exemplary embodiment of the presentinvention.

FIG. 4 is a layout view schematically showing a plurality of pixels anda wiring layer in a front display unit of an OLED display according toan exemplary embodiment of the present invention.

FIG. 5 is a cross-sectional view of a part of one pixel among aplurality of pixels shown in FIG. 4 according to an exemplary embodimentof the present invention.

FIG. 6 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 7 is a cross-sectional view of a part of one pixel among aplurality of pixels shown in FIG. 6 according to an exemplary embodimentof the present invention.

FIG. 8 is a layout view schematically showing a plurality of pixels anda wiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 9 is a cross-sectional view of a part of one pixel among aplurality of pixels shown in FIG. 8 according to an exemplary embodimentof the present invention.

FIG. 10 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 11 is a layout view schematically showing a plurality of pixels anda wiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 12 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 13 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 14 is a layout view schematically showing a plurality of pixels anda wiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 15 is a layout view schematically showing a plurality of pixels anda wiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 16 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 17 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 18 is a layout view schematically showing a plurality of pixels anda wiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 19 is a layout view schematically showing a plurality of pixels anda wiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 20 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 21 is a layout view schematically showing a plurality of pixels anda wiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

FIG. 22 is a layout view schematically showing a plurality of pixels, awiring layer, and a driving connecting member in a front display unit ofan OLED display according to an exemplary embodiment of the presentinvention.

FIG. 23 is a cross-sectional view of a part of one pixel among aplurality of pixels shown in FIG. 22 according to an exemplaryembodiment of the present invention.

FIG. 24 is a layout view schematically showing a plurality of pixels, awiring layer, and a driving connecting member in a right bending displayunit of an OLED display according to an exemplary embodiment of thepresent invention.

FIG. 25 is a graph showing a luminance change depending on a change of aviewing angle based on a front surface in a comparative example for anOLED without a projection and a reference example for an OLED having aprojection of a symmetric structure in a bending display unit.

FIG. 26 is a graph showing a red color coordinate change amountdepending on a change of a viewing angle based on a front surface in acomparative example for an OLED without a projection and a referenceexample for an OLED having a projection of a symmetric structure in abending display unit.

FIG. 27 is a graph showing a green color coordinate change amountdepending on a change of a viewing angle based on a front surface in acomparative example for an OLED without a projection and a referenceexample for an OLED having a projection of a symmetric structure in abending display unit.

FIG. 28 is a graph showing a blue color coordinate change amountdepending on a change of a viewing angle based on a front surface in acomparative example for an OLED without a projection and a referenceexample for an OLED having a projection of a symmetric structure in abending display unit.

FIG. 29 is a graph showing a luminance change depending on a change of aviewing angle based on a front surface in a comparative example for anOLED without a projection and an exemplary embodiment of the presentinvention for an OLED having a projection of an asymmetric structure ina bending display unit.

FIG. 30 is a graph showing a red color coordinate change amountdepending on a change of a viewing angle based on a front surface in acomparative example for an OLED without a projection and an exemplaryembodiment of the present invention for an OLED having a projection ofan asymmetric structure in a bending display unit.

FIG. 31 is a graph showing a green color coordinate change amountdepending on a change of a viewing angle based on a front surface in acomparative example for an OLED without a projection and an exemplaryembodiment of the present invention for an OLED having a projection ofan asymmetric structure in a bending display unit.

FIG. 32 is a graph showing a blue color coordinate change amountdepending on a change of a viewing angle based on a front surface in acomparative example for an OLED without a projection and an exemplaryembodiment of the present invention for an OLED having a projection ofan asymmetric structure in a bending display unit.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments of the present invention will be described morefully hereinafter with reference to the accompanying drawings. As thoseskilled in the art would realize, the described embodiments may bemodified in various different ways, and thus, should not be limited tothe embodiments set forth herein.

The same elements may be referred to with the same reference numeralsthroughout the specification.

In the drawings, the thickness of layers, films, panels, regions, etc.,may be exaggerated for clarity.

It will also be understood that when an element such as a layer, film,area, or plate is referred to as being “on” another element, it can bedirectly on the other element, or one or more intervening element mayalso be present.

Further, in the specification, the phrase “on a plane” may mean to viewan object portion from the top, and the phrase “on a cross-section” maymean to view a cross-section of the object portion which is verticallycut from the side.

FIG. 1 is a perspective view schematically showing an organic lightemitting diode (OLED) display in accordance with an exemplary embodimentof the present invention. FIG. 2 is a cross-sectional view of the OLEDdisplay shown in FIG. 1 according to an exemplary embodiment of thepresent invention.

Referring to FIG. 1 and FIG. 2, an OLED display 100 according to anexemplary embodiment of the present invention includes a substrate 10and a display unit 20 including a plurality of pixels P on the substrate10 for displaying an image.

The substrate 10 is made of a flexible material such as a polymer film,and at least a part of the substrate 10 is bent to form a curved portion12. The substrate 10 may include a flat portion 11 and the curvedportion 12 connected to at least one edge of the flat portion 11. Forexample, the substrate 10 may include the flat portion 11 and a pair ofcurved portions 12 respectively connected to a left side and a rightside or an upper side and a lower side of the flat portion 11. The twocurved portions 12 may have the same curvature, and centers ofcurvatures of the two curved portions 12 may be located at the sameside. In FIG. 1 and FIG. 2, a case in which the pair of curved portions12 is bent downwardly and connected to the left side and the right sideof the flat portion 11 is illustrated as an example.

The display unit 20 is bent along with the substrate 10, and includes afront display unit 21 for displaying the image on a front surfacethereof. The display unit 20 further includes bending display units 22and 23 that are bent at right and left sides of the front display unit21 for displaying the image on a side surface thereof. Hereinafter, itwill be described that the display unit disposed at the left side isreferred to as a left bending display unit 22 and the display unitdisposed at the right side is referred to as a right bending displayunit 23. In the present invention, the left side and the right side aredefined as such for convenience, however, the left side and the rightside may be changed depending on the viewing angle of reference. Forexample, an upper side and a lower side may be the left side and theright side, respectively.

The plurality of pixels P may be formed in the front display unit 21 andthe bending display unit 22 and 23 on the flat portion 11 and the curvedportion 12. The pixels P may have the same pattern. Each pixel P may bea minimum light emitting unit for displaying the image. The pixel P isconfigured of a pixel circuit and an OLED of which light emission iscontrolled by the pixel circuit.

For example, the OLED display 100 according to an exemplary embodimentof the present invention consists of the front display unit 21 and thebending display units 22 and 23 to minimizes a dead space in which theimage is not shown, thereby maximizing the amount of space on which todisplay the image. In other words, the size of the display unit 20 isincreased.

The display unit 20 may be covered and sealed by a thin filmencapsulation layer. The thin film encapsulation layer suppressesdeterioration of the OLED caused by moisture and oxygen contained inexternal air.

Users' eyes are typically located at the center and in front of thedisplay unit 20 when viewing images on the display unit 20. Since thecurve portion 12 is bent with a predetermined curvature at an edge ofthe flat portion 11, the users see light emitted from the flat portion11 toward the front thereof and light emitted from the curved portion 12toward the side thereof. In this case, the light emitted from thebending display units 22 and 23 toward the side has a whitecharacteristic different from the light emitted from the front displayunit 21 toward the front. In other words, a color quality difference isgenerated. This color quality difference may worsen due to a step of awiring layer in a high resolution application. The area of the lightemission portion is wide before the high resolution application suchthat a luminance or color change non-uniformity has a negligible levelalthough the step increases. However, the luminance difference or thecolor change is largely visible even if there is only a small flexion ofthe display unit 21 while in the high resolution application, since thelight emission portion area becomes narrow.

The OLED display 100 according to an exemplary embodiment of the presentinvention positions the wiring layer on the substrate 10 to reduce anangle of the light emitted from the curved portion to the side, therebyincreasing a WAD characteristic. Hereinafter, various exemplaryembodiments describing the position of the wiring layer in the lightemission portion will be provided.

FIG. 3 is a layout view schematically showing a plurality of pixels ofan OLED display according to an exemplary embodiment of the presentinvention.

Referring to FIG. 3, the display unit 20 includes a pixel definitionlayer 350 having an opening 352. The OLED is formed in the opening 352,and light is emitted from the OLED such the opening 352 corresponds to aregion defining a light emission portion.

In the present exemplary embodiment, a first light emission portioncorresponding to a red pixel R and a third light emission portioncorresponding to a blue pixel B are alternately disposed in a first row1N, and a plurality of second light emission portions corresponding to agreen pixel G are disposed to be separated by a predetermined intervalin a second row 2N adjacent to the first row 1N. The third lightemission portion corresponding to the blue pixel B and the first lightemission portion corresponding to the red pixel R are alternatelydisposed in a third row 3N adjacent to the second row 2N, while aplurality of second light emission portions corresponding to the greenpixel G are disposed to be separated with a predetermined interval in afourth row 4N adjacent to the third row 3N. As shown in a fifth row 5Nand a sixth row 6N, and the arrangement of the pixels and the lightemission portions may be repeated. In this case, the first lightemission portion corresponding to the red pixel R and the third lightemission portion corresponding to the blue pixel B may be formed to belarger than the second light emission portion corresponding to the greenpixel G.

The first light emission portion corresponding to the red pixel Rdisposed in the first row 1N and the third light emission portioncorresponding to the blue pixel B disposed in the first row 1N, and thesecond light emission portion corresponding to the green pixel Gdisposed in the second row 2N are alternately disposed. Accordingly, thefirst light emission portion corresponding to the red pixel R and thethird light emission portion corresponding to the blue pixel B arealternately disposed in a first column 1M, and the plurality of secondlight emission portions corresponding to the green pixel G are disposedto be separated with a predetermined interval in a second column 2Madjacent to the first column 1M. Similarly, the third light emissionportion corresponding to the blue pixel B and the first light emissionportion corresponding to the red pixel R are alternately disposed in thethird column 3M adjacent to the second column 2M, and the plurality ofsecond light emission portions corresponding to the green pixel G aredisposed to be separated with a predetermined interval in the fourthcolumn 4M adjacent to the third column 3M. As can be seen from columns4M, 5M, 6M and 7M in FIG. 3, the arrangement of the pixels and the lightemission portions may be repeated.

This pixel arrangement structure is referred to as a pentile matrix. Insuch a structure, high resolution images may be realized by pixels of asmall number by applying rendering driving for displaying a color andsharing an adjacent pixel.

FIG. 4 is a layout view schematically showing a plurality of pixels anda wiring layer in a front display unit of an OLED display according toan exemplary embodiment of the present invention. FIG. 5 is across-sectional view of a part of one pixel among a plurality of pixelsshown in FIG. 4 according to an exemplary embodiment of the presentinvention.

Referring to FIG. 4, on the front display unit 21, the first lightemission portion, the second light emission portion, and the third lightemission portion that respectively correspond to the red pixel R, thegreen pixel G, and the blue pixel B are disposed in the opening 352 ofthe pixel definition layer 350. In the front display unit 21 disposed onthe flat portion of the substrate, a plurality of wiring layers 170passing through the light emission portions are formed, and the wiringlayers 170 may include a data line 171 and a driving voltage line 172.In the front display unit 21, the wiring layers 170 may overlap thefirst light emission portion, the second light emission portion, and thethird light emission portion, and the wiring layers 170 may besymmetrically disposed in each light emission portion. In other words, aregion that includes the wiring layer 170 may have a symmetric shape inthe opening 352.

Referring to FIG. 5, the OLED display according to the present exemplaryembodiment includes insulating layers, elements, and electrodes to formthe OLED display disposed on the substrate 10.

The substrate 10 may be made of a flexible material such as polyimide,polyethylene terephthalate, polyether sulfone, polyacrylate,polyethylene naphthalate, polyphenylene sulfide, triacetyl cellulose,and the like. However, it is not limited thereto.

A buffer layer 120 for preventing penetration of an impurity andproviding planarization of a surface may be disposed on the substrate10. The buffer layer 120 may be formed of a material such as siliconnitride, silicon oxide, or silicon oxynitride, however the buffer layer120 may be omitted depending on a type and/or a process condition of thesubstrate 10.

A light emission control channel 155, and a light emission controlsource electrode 156 and a light emission control drain electrode 157 atrespective sides of the light emission control channel 155, are disposedon the buffer layer 120. A gate insulating layer 140 is disposed on thebuffer layer 120, and a light emission control gate electrode 124 isdisposed on the gate insulating layer 140. An interlayer insulatinglayer 160 is disposed on the light emission control gate electrode 124.The interlayer insulating layer 160 may be formed of silicon nitride,silicon oxide, or the like.

The light emission control gate electrode 124, the light emissioncontrol source electrode 156, the light emission control drain electrode157, and the light emission control channel 155 form a light emissioncontrol transistor 154. FIG. 5 only shows the light emission controltransistor 154, however the light emission control transistor 154 may beconnected to a driving transistor. In addition, the OLED displayaccording to the present exemplary embodiment may include a switchingtransistor, a compensation transistor, an initialization transistor, anoperation control transistor, and a bypass transistor, and may alsoinclude a plurality of capacitors and scan lines. The present exemplaryembodiment is not limited thereto, and a number of the transistors and anumber of the capacitors maybe variously changed.

The interlayer insulating layer 160 has a first contact hole 66, and thefirst contact hole 66 may be filled with a pixel connecting member 175.A data metal layer including the data line 171, the driving voltage line172, and the pixel connecting member 175 is disposed on the interlayerinsulating layer 160. The data metal layer may be formed a single layermade of a metal layer including one of copper, a copper alloy, aluminum,an aluminum alloy, molybdenum, a molybdenum alloy, titanium, and atitanium alloy, or multiple layers including the metal layer. Forexample, a titanium/aluminum/titanium triple layer, or amolybdenum/aluminum/molybdenum or molybdenum/copper/molybdenum triplelayer, may be applied.

The data line 171 transmits a data signal, and the data line 171 may beconnected to a source electrode of the switching transistor. The drivingvoltage line 172 transmits a driving voltage ELVDD and may be parallelto the data line 171.

A passivation layer 181 is disposed on the data metal layer includingthe data line 171, the driving voltage line 172, and the pixelconnecting member 175. The passivation layer 181 covers the data metallayer. In the present exemplary embodiment, the passivation layer 181overlaps the wiring layers 170 including the data line 171 and thedriving voltage line 172. The upper surface of a part of the passivationlayer 181 overlapping the data line 171 has a curved portion by a stepof the data line 171, and the upper surface of a part of the passivationlayer 181 overlapping the driving voltage line 172 has the curvedportion by the step of the driving voltage line 172. The step of avoltage line may correspond to a thickness of the voltage line in thevertical direction of FIG. 5. The curved portion of the passivationlayer 181 forms a projection HP in the OLED that is described below.

The passivation layer 181 according to the present exemplary embodimenthas a thickness of about 15,000 angstroms or less. If the passivationlayer 181 is very thick, the above-described curved portion of the uppersurface of the passivation layer 181 may disappear throughplanarization, thereby the following projection HP may not be formed.

The passivation layer 181 may be formed of an organic material such as apolyacryl-based resin, a polyimide-based resin, or a stacked structureof an organic material and an inorganic material.

The OLED and the pixel definition layer 350 are disposed on thepassivation layer 181. The OLED includes a pixel electrode 191, alight-emitting diode display layer 360, and a common electrode 270. Thepixel electrode 191 may be a reflecting electrode, and the commonelectrode 270 may be a transflective electrode.

In the present invention, the reflecting electrode may be an electrodeincluding a material having a characteristic of reflecting light emittedfrom the light-emitting diode display layer 360 to the common electrode270. The reflection characteristic may mean that reflectivity ofincident light is about 70% or more to about 100% or less, or about 80%or more to about 100% or less.

The pixel electrode 191 may include silver (Ag), aluminum (Al), chromium(Cr), molybdenum (Mo), tungsten (W), titanium (Ti), gold (Au), palladium(Pd), or alloys thereof to be used as the reflection layer while havingthe function of an anode, and may be a triple layer structure of silver(Ag)/indium tin oxide (ITO)/silver (Ag) or indium tin oxide (ITO)/silver(Ag)/indium tin oxide (ITO).

In the present invention, the transflective electrode may be anelectrode including a material having a transflective characteristic fortransmitting part of the light incident to the common electrode 270 andreflecting a remaining part of the light to the pixel electrode 191.Here, the transflective characteristic may mean that the reflectivity ofthe incident light is about 0.1% or more to about 70% or less, or about30% or more to about 50% or less.

The common electrode 270 may include silver (Ag), magnesium (Mg),aluminum (Al), chromium (Cr), molybdenum (Mo), tungsten (W), titanium(Ti), gold (Au), palladium (Pd), ytterbium (Yb), or alloys thereof.

The pixel electrode 191 may be connected to the pixel connecting member175 through a second contact hole 86 formed in the passivation layer181. The pixel electrode 191 receives an electrical signal from thelight emission control drain electrode 157 connected to the pixelconnecting member 175 to transmit an electron or a hole to thelight-emitting diode display layer 360. The electron or the hole iscombined with a hole or an electron supplied from the common electrode270 in the emission layer of the light-emitting diode display layer 360,thereby forming an exciton. Light may be emitted while the exciton isstabilized.

The pixel definition layer 350 disposed on the passivation layer 181 hasan opening 352 corresponding to the light emission portion of the pixel.The pixel electrode 191 may correspond to the opening 352 of the pixeldefinition layer 350. However, the pixel electrode 191 is not alwaysdisposed only in the opening 352 of the pixel definition layer 350. Forexample, as shown in FIG. 5, part of the pixel electrode 191 may bedisposed under the pixel definition layer 350 so that the pixeldefinition layer 350 overlaps the pixel definition layer 350.

The light-emitting diode display layer 360 may be disposed on the pixelelectrode 191 disposed in the opening 352 of the pixel definition layer350. In this case, the light-emitting diode display layer 360 mayinclude an emission layer for generating the exciton, a hole injectionlayer between the emission layer and the pixel electrode 191, a holetransport layer, an electron injection layer between the emission layerand the common electrode 270, and an electron transport layer.

The emission layer may be at least one of a red organic emission layerfor emitting red, a blue organic emission layer for emitting blue, and agreen organic emission layer for emitting green. In this case, the redorganic emission layer, the blue organic emission layer, and the greenorganic emission layer are respectively formed in the red pixel, thegreen pixel, and the blue pixel, thereby realizing a color image. As avariation of the present exemplary embodiment, the emission layer may becombined with a plurality of layers representing different colors toemit white, and the plurality of layers may include a structure in whichtwo layers or three layers are deposited. In this case, color may berealized by forming a red color filter, a green color filter, and a bluecolor filter for each pixel.

The OLED display according to the present exemplary embodiment, mayinclude an encapsulation layer disposed on the common electrode 270.

In the present exemplary embodiment, the OLED has the projection HP inthe light emission portion corresponding to the opening 352. Theprojection HP overlaps the wiring layer 170 disposed under thepassivation layer 181, and the wiring layer 170 includes the data line171 and the driving voltage line 172 separated from each other. As shownin FIG. 5, two projections HP are formed in the light emission portioncorresponding to the opening 352, one over line 171 and one over line172. Two projections HP may be symmetric with respect to each other inthe light emission portion. Since the projection HP in the front displayunit on the flat portion of the substrate 10 is symmetrically disposedin the light emission portion, a color shift phenomenon that may begenerated in a front portion of a display may be reduced.

The structure including the OLED shown in FIG. 5 shows the part of onepixel among the plurality of pixels of FIG. 4. It is to be understood,however, that this structure may be applied to all of the pixelsdisposed in the front display unit 21 of FIG. 4. However, since thegreen pixel G is smaller than the red pixel R and the blue pixel B, thewidth of the opening 352 shown in FIG. 5 may be changed depending on thepixel size used.

FIG. 6 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention. FIG. 7 isa cross-sectional view of a part of one pixel among a plurality ofpixels shown in FIG. 6 according to an exemplary embodiment of thepresent invention.

Referring to FIG. 6, in the left bending display unit 22, the firstlight emission portion, the second light emission portion, and the thirdlight emission portion respectively corresponding to the red pixel R,the green pixel G, and the blue pixel B are disposed in the opening 352of the pixel definition layer 350. In the left bending display unit 22disposed on the curved portion 21 of the substrate 10, the plurality ofwiring layers 170 passing through the light emission portion are formed,and the wiring layers 170 may include the data line 171 and the drivingvoltage line 172. In the left bending display unit 22, the wiring layers170 overlap the first light emission portion, the second light emissionportion, and the third light emission portion, and the wiring layers 170may be disposed to be asymmetric in each light emission portion. Inother words, the region occupied with the wiring layer 170 in theopening 352 may have the asymmetric shape. Particularly, as shown inFIG. 2, when the direction toward the left curved portion 12 in the flatportion 11 is a first direction d1, the wiring layers 170 in FIG. 6 arelocated to be biased in the first direction d1 in each light emissionportion.

Referring to FIG. 7, the upper surface of the passivation layer 181overlapping the wiring layer 170 has the curved portion, and the curvedportion of the passivation layer 181 forms the projection HP in theOLED. The projection HP is asymmetrically disposed to be biased in thefirst direction d1 in the light emission portion corresponding to theopening 352. Thus, since the projection HP generated in the bendingdisplay unit is asymmetrically disposed to be biased in the firstdirection d1, the angle of the light emitted from the side from thecurved portion is reduced such that the WAD characteristic may beimproved.

As above-described, in addition to the asymmetric arrangement structureof the wiring layers 170 and the projection HP, the configurationsdisposed in the left bending display unit 22 are the same as orsubstantially the same as the configurations of the front display unit21 described in FIG. 5 and FIG. 6. Therefore, content described inreference to FIG. 5 and FIG. 6 may be applied to the left bendingdisplay unit 22.

The structure including the OLED shown in FIG. 7 shows the part of onepixel among the plurality of pixels of FIG. 6. It is to be understood,however, that the structure shown in FIG. 7 may be applied to all of thepixels disposed in the left bending display unit 22 of FIG. 6. However,since the green pixel G is smaller than the red pixel R and the bluepixel B, the width of the opening 352 shown in FIG. 7 may be changeddepending on the size of a pixel. In addition, as shown in FIG. 6, inthe case of the green pixel G, only the driving voltage line 172 amongthe wiring layers 170 may overlap the light emission portioncorresponding to the opening 352.

FIG. 8 is a layout view schematically showing a plurality of pixels anda wiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention. FIG. 9 isa cross-sectional view of a part of one pixel among a plurality ofpixels shown in FIG. 8 according to an exemplary embodiment of thepresent invention.

The exemplary embodiment to be described in reference to FIG. 8 and FIG.9 is almost the same as the exemplary embodiment described in referenceto FIG. 6 and FIG. 7. However, as shown in FIG. 8 and FIG. 9, the wiringlayer 170 and the projection HP are disposed to be biased in a seconddirection d2 opposite to the first direction d1. The second direction d2is substantially opposite to the first direction d1. For example, asshown in FIG. 2, the second direction d2 is a direction toward the rightcurved portion 12 in the flat portion 11. In addition, since theprojection HP generated in the right bending display unit 23 accordingto the present exemplary embodiment is disposed to be asymmetricallybiased to the second direction d2, the angle of the light emitted fromthe side from the curved portion is reduced, thereby improving the WADcharacteristic.

In addition to the above-described differences, the contents describedin reference to FIG. 6 and FIG. 7 may be applied to the presentexemplary embodiment.

In the exemplary embodiments described in FIG. 6 to FIG. 9, since theOLED having the asymmetric projection is formed in the red pixel, thegreen pixel, and the blue pixel, there is provided a structure thatcompensated for a phenomenon in which the white becomes reddish,greenish, or bluish due to a red color shift, a green color shift, and ablue color shift. In this case, the thickness of the projection in eachpixel may be controlled to reduce the color shift phenomenon dependingon the side viewing angle for the color emitted from the OLED.

FIG. 10 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention. FIG. 11is a layout view schematically showing a plurality of pixels and awiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

Referring to FIG. 10, in the left bending display unit 22, the firstlight emission portion, the second light emission portion, and the thirdlight emission portion respectively corresponding to the red pixel R,the green pixel G, and the blue pixel B are disposed in the opening 352of the pixel definition layer 350. In the left bending display unit 22disposed on the curved portion 12 of the substrate 10, the plurality ofwiring layers 170 passing through the light emission portion are formed,and the wiring layer 170 may include the data line 171 and the drivingvoltage line 172. In the left bending display unit 22, the wiring layers170 overlap the first light emission portion, the second light emissionportion, and the third light emission portion, and the wiring layers 170are asymmetrically disposed to be biased in the first direction d1 inthe first light emission portion and the third light emission portion;however, the wiring layers 170 may be symmetrically disposed in thesecond light emission portion. The present exemplary embodiment providesa structure that compensates for the phenomenon in that the color whitebecomes reddish or bluish due to the red color shift or the blue colorshift.

Referring to FIG. 11, like the exemplary embodiment of FIG. 10, thewiring layer 170 is asymmetrically disposed in the first light emissionportion and the third light emission portion; however, the wiring layer170 is symmetrically disposed in the second light emission portion,thereby forming the red compensation and blue compensation structure.However, the exemplary embodiment of FIG. 11 provides the compensationstructure in the right bending display unit 23, and thus, the wiringlayer 170 is disposed to be biased in the second direction d2 in thefirst light emission portion and the third light emission portion toform the asymmetric structure.

FIG. 12 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention. FIG. 13is a layout view schematically showing a plurality of pixels and awiring layer in a left bending display unit of an OLED display accordingto an exemplary embodiment of the present invention.

Referring to FIG. 12, the wiring layer 170 is asymmetrically disposed tobe biased in the first direction d1 in the first light emission portion,and the wiring layer 170 is symmetrically disposed in the second lightemission portion and the third light emission portion to be the redcompensation structure. To realize the red compensation structure, theinterval between the data line 171 and the driving voltage line 172 inthe first light emission portion and the interval between the data line171 and the driving voltage line 172 in the third light emission portionmay be different from each other. As shown in FIG. 12, the intervalbetween the data line 171 and the driving voltage line 172 in the thirdlight emission portion may be larger than the interval between the dataline 171 and the driving voltage line 172 in the first light emissionportion. Thus, as the interval of the wiring layer 170 is differentiateddepending on its position, the driving voltage line 172 between thefirst light emission portion (R) and the third light emission portion(B) (which are adjacent to each other vertically as shown in FIG. 12)may have a bent portion.

Referring to FIG. 13, like the exemplary embodiment of FIG. 12, thewiring layer 170 is asymmetrically disposed to be biased in the firstdirection d1 in the first light emission portion, and the wiring layer170 is symmetrically disposed in the second light emission portion andthe third light emission portion to be the red compensation structure.However, differently from that shown in FIG. 12, the interval betweenthe data line 171 and the driving voltage line 172 in the first lightemission portion and the interval between the data line 171 and thedriving voltage line 172 in the third light emission portion are equalto each other. In the present exemplary embodiment, to realize the redcompensation structure, the first light emission portion (R) and thethird light emission portion (B) are arranged to deviate from each otherwith respect to a vertical axis. In other words, as shown on FIG. 13,the first light emission portion is disposed more to the right of thevertical axis, whereas the third light emission portion is disposed moreto the left of the vertical axis. Here, the vertical axis may be adirection substantially perpendicular to the first direction d1.

FIG. 14 is a layout view schematically showing a plurality of pixels anda wiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention. FIG. 15is a layout view schematically showing a plurality of pixels and awiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

Referring to FIG. 14, like the exemplary embodiment of FIG. 12, thewiring layer 170 is asymmetrically disposed in the first light emissionportion, and the wiring layer 170 is symmetrically disposed in thesecond light emission portion and the third light emission portion to bethe red compensation structure. However, the exemplary embodiment ofFIG. 14 is the compensation structure of the right bending display unit23, and the wiring layer 170 is disposed to be biased in the seconddirection d2 in the first light emission portion formed with theasymmetric structure. Thus, as the interval of the wiring layer 170 isdifferentiated depending on its position, the data line 171 between thefirst light emission portion (R) and the third light emission portion(B) vertically adjacent with respect to each other may have a bentportion.

Referring to FIG. 15, like the exemplary embodiment of FIG. 14, thewiring layer 170 is disposed to be asymmetrically biased in the seconddirection d2 in the first light emission portion, and the wiring layer170 is symmetrically disposed in the second light emission portion andthe third light emission portion to be the red compensation structure.However, differently from that shown in FIG. 14, the interval betweenthe data line 171 and the driving voltage line 172 in the third lightemission portion and the interval between the data line 171 and thedriving voltage line 172 in the first light emission portion are equalto each other. In the present exemplary embodiment, to realize the redcompensation structure, the first light emission portion and the thirdlight emission portion deviate from each other with respect to avertical axis. Here, the vertical axis may be a direction substantiallyperpendicular to the second direction d2.

FIG. 16 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention. FIG. 17is a layout view schematically showing a plurality of pixels and awiring layer in a left bending display unit of an OLED display accordingto an exemplary embodiment of the present invention.

Referring to FIG. 16, the wiring layer 170 is disposed to beasymmetrically biased in the first direction d1 in the third lightemission portion, and the wiring layer 170 is symmetrically disposed inthe first light emission portion and the second light emission portionto be the blue compensation structure. To realize the blue compensationstructure, the interval between the data line 171 and the drivingvoltage line 172 in the first light emission portion and the intervalbetween the data line 171 and the driving voltage line 172 in the thirdlight emission portion may be different from each other. As shown inFIG. 16, the interval between the data line 171 and the driving voltageline 172 in the third light emission portion may be narrower than theinterval between the data line 171 and the driving voltage line 172 inthe first light emission portion. Thus, as the interval of the wiringlayer 170 is differentiated depending on its position, the drivingvoltage line 172 between the first light emission portion and the thirdlight emission portion that are vertically adjacent to each other mayhave a bent portion.

Referring to FIG. 17, like the exemplary embodiment of FIG. 16, thewiring layer 170 is asymmetrically disposed to be biased in the firstdirection d1 in the third light emission portion, and the wiring layer170 is symmetrically disposed in the first light emission portion andthe second light emission portion to be the blue compensation structure.However, differently from that shown in FIG. 16, the interval betweenthe data line 171 and the driving voltage line 172 in the first lightemission portion and the interval between the data line 171 and thedriving voltage line 172 in the third light emission portion are equalto each other. In the present exemplary embodiment, to realize the bluecompensation structure, the first light emission portion and the thirdlight emission portion deviate from each other with respect to thevertical axis. Here, the vertical axis may be a direction substantiallyperpendicular to the first direction d1.

FIG. 18 is a layout view schematically showing a plurality of pixels anda wiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention. FIG. 19is a layout view schematically showing a plurality of pixels and awiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

Referring to FIG. 18, like the exemplary embodiment of FIG. 16, thewiring layer 170 is asymmetrically disposed in the third light emissionportion, and the wiring layer 170 is symmetrically disposed in the firstlight emission portion and the second light emission portion to be theblue compensation structure. However, the exemplary embodiment of FIG.18 is the compensation structure of the right bending display unit 23,and to form the compensation structure, the wiring layer 170 is disposedto be biased in the second direction d2 in the third light emissionportion. Thus, as the interval of the wiring layer 170 is differentiateddepending on its position, the data line 171 between the first lightemission portion and the third light emission portion verticallyadjacent to each other may have the bent portion.

Referring to FIG. 19, like the exemplary embodiment of FIG. 18, thewiring layer 170 is asymmetrically disposed to be biased in the seconddirection d2 in the third light emission portion, and the wiring layer170 is symmetrically disposed in the first light emission portion andthe second light emission portion to be the blue compensation structure.However, differently from that shown in FIG. 18, the interval betweenthe data line 171 and the driving voltage line 172 in the first lightemission portion and the interval between the data line 171 and thedriving voltage line 172 in the third light emission portion are equalto each other. In the present exemplary embodiment, to realize the bluecompensation structure, the first light emission portion and the thirdlight emission portion deviate from each other with respect to thevertical axis. Here, the vertical axis may be the directionsubstantially perpendicular to the second direction d2.

FIG. 20 is a layout view schematically showing a plurality of pixels anda wiring layer in a left bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention. FIG. 21is a layout view schematically showing a plurality of pixels and awiring layer in a right bending display unit of an OLED displayaccording to an exemplary embodiment of the present invention.

Referring to FIG. 20, the wiring layer 170 is symmetrically disposed inthe first light emission portion and the third light emission portion,and the wiring layer 170 is asymmetrically disposed to be biased in thefirst direction d1 in the second light emission portion to be the greencompensation structure. To realize the green compensation structure, thedriving voltage line 172 of the wiring layer 170 may only be disposed tobe biased in the first direction d1 in the second light emissionportion, and the data line 171 may not pass through the second lightemission portion.

Referring to FIG. 21, like the exemplary embodiment of FIG. 20, thewiring layer 170 is symmetrically disposed in the first light emissionportion and the third light emission portion, and the wiring layer 170is asymmetrically disposed in the second light emission portion to bethe green compensation structure. However, the exemplary embodiment ofthe FIG. 21 is the compensation structure of the right bending displayunit 23, and to form the compensation structure, the wiring layer 170 isdisposed to be biased in the second direction d2 in the second lightemission portion. In addition, to realize the compensation structure,the data line 171 of the wiring layer 170 may only be disposed to bebiased in the second direction d2 in the second light emission portion,and the driving voltage line 172 may not pass through the second lightemission portion.

FIG. 22 is a layout view schematically showing a plurality of pixels, awiring layer, and a driving connecting member in a front display unit ofan OLED display according to an exemplary embodiment of the presentinvention. The exemplary embodiment described in FIG. 22 is almost thesame as the exemplary embodiment described in the FIG. 4 such thatmainly differences will be described below.

Referring to FIG. 22, in addition to the elements of FIG. 4, a drivingconnecting member 174 may be disposed in the front display unit 21. Thedriving connecting member 174 is disposed in the same layer as thewiring layer 170 including the data line 171 and the driving voltageline 172.

FIG. 23 is a cross-sectional view of a part of one pixel among aplurality of pixels shown in FIG. 22 according to an exemplaryembodiment of the present invention. The exemplary embodiment describedin FIG. 23 is almost the same as the exemplary embodiment described inthe FIG. 5 such that mainly differences will be described below.

Referring to FIG. 23, a driving transistor 164 includes a drivingchannel 165, a driving gate electrode 134, a driving source electrode166, and a driving drain electrode 167. The driving gate electrode 134overlaps the driving channel 165, and the driving source electrode 166and the driving drain electrode 167 are formed on both sides of thedriving channel 165. The driving gate electrode 134 is connected to thedriving connecting member 174 through a driving contact hole 61. Thedriving gate electrode 134 is disposed in the same layer as the lightemission control gate electrode 124, and the driving connecting member174 is disposed in the same layer as the wiring layer 170.

FIG. 24 is a layout view schematically showing a plurality of pixels, awiring layer, and a driving connecting member in a right bending displayunit of an OLED display according to an exemplary embodiment of thepresent invention. The exemplary embodiment described in FIG. 24 isalmost the same as the exemplary embodiment described in the FIG. 21such that mainly differences will be described below.

Referring to FIG. 24, like the exemplary embodiment of FIG. 21, thesymmetric structure is formed in the first light emission portion andthe third light emission portion, however the asymmetric structure isformed in the second light emission portion to be the green compensationstructure. To form the symmetric structure in the first light emissionportion and the third light emission portion, like the exemplaryembodiment of FIG. 21, the driving connecting member 174 and the dataline 171 substantially form the symmetric structure in the first lightemission portion and the third light emission portion of the presentexemplary embodiment.

In the exemplary embodiment of FIG. 24, the green compensation structureis formed by the wiring layer 170 and the driving connecting member 174.It is to be understood, however, that such a variation may be applied tothe red compensation structure and the blue compensation structure andsuch a variation may also be applied to the left bending display unit aswell as the right bending display unit.

Next, a luminance change and a color coordinate change amount dependingon the change of the viewing angle based on the front side of a displaywill be described in a comparative example with reference to the presentinvention. For example, FIGS. 25 to 32 illustrate Reference Example 1,Reference Example 2, Exemplary Embodiment 1, and Exemplary Embodiment 2.A color change amount corresponding to a Y-axis of FIG. 26 to FIG. 28,and FIG. 30 to FIG. 32, represents the color coordinate change amount.

Reference Example 1 is a case where the angle of the projection is about3 degrees in the red pixel, the angle of the projection is about 4degrees in the green pixel and the blue pixel, and the wiring layerforming these angles is symmetrically disposed in the light emissionportion. Reference Example 2 is a case where the angle of the projectionis about 10 degrees in the red pixel, the green pixel, and the bluepixel, and the wiring layer to form this angle is symmetrically disposedin the light emission portion. Exemplary Embodiment 1 is a case wherethe angle of the projection is about 3 degrees in the red pixel, theangle of the projection is about 4 degrees in the green pixel and theblue pixel, and the wiring layer forming these angles is asymmetricallydisposed in the light emission portion of the right bending displayunit. Exemplary Embodiment 2 is a case where the angle of the projectionis about 10 degrees in the red pixel, the green pixel, and the bluepixel, and the wiring layer to form this angle is symmetrically disposedin the light emission portion of the right bending display unit. Theluminance change and the color coordinate change amount that aremeasured in Exemplary Embodiments 1 and 2 represent the light emittedfrom the left side when viewing the user views the OLED display. Here,the angle of the projection may be a tangent value when a first side isa bottom side and a second side is a height in a right triangle made ofthe first side corresponding to the entire width of the projection andthe second side corresponding to the height of the projection.

FIG. 25 is a graph showing a luminance change depending on a change of aviewing angle at a front surface in a comparative example for an OLEDwithout a projection and Reference Examples 1 and 2 for an OLED having aprojection of a symmetric structure in a bending display unit.

Referring to FIG. 25, a large difference for the luminance changemeasured depending on the viewing angle in the red pixel does not appearin the comparative example and Reference Example 1, however a slightlylarger difference for the luminance change appears in Reference Example2.

FIG. 26 is a graph showing a red color coordinate change amountdepending on a change of a viewing angle at a front surface in acomparative example for an OLED without a projection and ReferenceExamples 1 and 2 for an OLED having a projection of a symmetricstructure in a bending display unit. FIG. 27 is a graph showing a greencolor coordinate change amount depending on a change of a viewing angleat a front surface in a comparative example for an OLED without aprojection and Reference Examples 1 and 2 for an OLED having aprojection of a symmetric structure in a bending display unit. FIG. 28is a graph showing a blue color coordinate change amount depending on achange of a viewing angle at a front surface in a comparative examplefor an OLED without a projection and Reference Examples 1 and 2 for anOLED having a projection of a symmetric structure in a bending displayunit.

Referring to FIG. 26 to FIG. 28, it may be confirmed almost nodifference exists for the color coordinate change amount in thecomparative example and Reference Examples 1 and 2 in the viewing angleof 20 degrees or less, however as the viewing angle is increased, thecolor coordinate change amount is small in Reference Example 2 comparedwith the comparative example and Reference Example 1. In addition,comparing Reference Example 1 and Reference Example 2, even when theOLED has the projection of the symmetric structure, it may be confirmedthat the angle of the projection is increased, and the color coordinatechange amount is small.

FIG. 29 is a graph showing a luminance change depending on a change of aviewing angle at a front surface in a comparative example for an OLEDwithout a projection and Exemplary Embodiments 1 and 2 for an OLEDhaving a projection of an asymmetric structure in a bending displayunit.

Referring to FIG. 29, the luminance change measured depending on theviewing angle in the red pixel is smaller in Exemplary Embodiment 1compared with the comparative example and is smaller in ExemplaryEmbodiment 2 compared with Exemplary Embodiment 1. Compared withReference Examples 1 and 2 described in FIG. 25, it may be confirmedthat the luminance change is small in Exemplary Embodiments 1 and 2.

FIG. 30 is a graph showing a red color coordinate change amountdepending on a change of a viewing angle at a front surface in acomparative example for an OLED without a projection and ExemplaryEmbodiments 1 and 2 for an OLED having a projection of an asymmetricstructure in a bending display unit. FIG. 31 is a graph showing a greencolor coordinate change amount depending on a change of a viewing angleat a front surface in a comparative example for an OLED without aprojection and Exemplary Embodiments 1 and 2 for an OLED having aprojection of an asymmetric structure in a bending display unit. FIG. 32is a graph showing a blue color coordinate change amount depending on achange of a viewing angle at a front surface in a comparative examplefor an OLED without a projection and Exemplary Embodiments 1 and 2 foran OLED having a projection of an asymmetric structure in a bendingdisplay unit.

Referring to FIG. 30 to FIG. 32, it may be confirmed that the colorcoordinate change amount is small in Exemplary Embodiments 1 and 2compared with the comparative example in most viewing angles. Inaddition, comparing Exemplary Embodiment 1 and Exemplary Embodiment 2,even when the OLED has the projection of the asymmetric structure, theangle of the projection is increased, and it may be confirmed that thecolor coordinate change amount is small. As can be seen, the effect islarger as the angle of the projection is increased, however theelectrical characteristic may worsen by the step (e.g., of a wiring lineof a wiring layer) if the angle is very large. Thus, optimization may berequired by considering the luminance change and the color coordinatechange amount, as well as the electrical characteristic.

In an OLED display, as the observation angle of the observer isincreased, when the observer is moved from the front of the display tothe side, a color shift is generated such that a phenomenon in which acolor is recognized as another color is generated. This phenomenon mayworsen because of the curve due to the step of the wiring layer.Further, even if a clear color screen is realized at the front of theOLED display, as the observation angle is moved from the front to theside, the display quality may deteriorate due to the color shiftphenomenon, however the OLED display according to an exemplaryembodiment of the present invention may control the position of thewiring layer such that the WAD characteristic may be improved orsmoothened by specifying the particular color. In other words, in anOLED display including a curved portion and a flat portion, a colorquality difference between the flat portion and the curved portionrecognized by users is minimized. In addition, process design forforming a conventional wiring layer is only changed by the presentinvention to control the position of the wiring layer such that anadditional process is not required. This may reduce manufacturing costs.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the present invention as defined by the following claims.

What is claimed is:
 1. A display device, comprising: a substrateincluding a curved portion and a flat portion, wherein the curvedportion is bent and connected to a side of the flat portion; aninsulating layer disposed on the substrate; and a first organic lightemitting diode disposed on the insulating layer and having a firstprojection; and a second organic light emitting diode having a secondprojection, wherein a light emission portion is disposed in the curvedportion and the flat portion, the first projection which overlaps thelight emission portion of the curved portion and disposed in a firstopening of a pixel definition layer is asymmetrically disposed withrespect to a line passing through the middle of the first opening, andthe second projection which overlaps the light emission portion of theflat portion and disposed in a second opening of the pixel definitionlayer is symmetrically disposed with respect to a line passing throughthe middle of the second opening.
 2. The display device of claim 1,further comprising a wiring layer disposed between the substrate and theinsulating layer and disposed in the curved portion and the flatportion, wherein the wiring layer disposed in the curved portionoverlaps the first projection, and the wiring layer disposed in the flatportion overlaps the second projection.
 3. The display device of claim2, wherein the light emission portion disposed in the curved portionincludes a first light emission portion, a second light emissionportion, and a third light emission portion, the first light emissionportion, the second light emission portion, and the third light emissionportion respectively corresponding to one of a red pixel, a green pixel,and a blue pixel, the light emission portion in the first opening is thefirst light emission portion, and the first projection also overlaps thethird light emission portion in a third opening of the pixel definitionlayer and is asymmetrically disposed with respect to a line passingthrough the middle of the third opening.
 4. The display device of claim3, wherein the first projection includes a pair of first bumps and apair of third bumps, the pair of first bumps is disposed asymmetricallywith respect to the line passing through the middle of the firstopening, and the pair of third bumps is disposed asymmetrically withrespect to the line passing through the middle of the third opening. 5.The display device of claim 3, wherein the first projection alsooverlaps the second light emission portion in a fourth opening of thepixel definition layer and is asymmetrically disposed with respect to aline passing through the middle of the fourth opening.
 6. The displaydevice of claim 5, wherein the first projection includes a pair of firstbumps, a pair of second bumps and a pair of third bumps, the pair offirst bumps is disposed asymmetrically with respect to the line passingthrough the middle of the first opening, the pair of second bumps isdisposed asymmetrically with respect to the line passing through themiddle of the fourth opening, and the pair of third bumps is disposedasymmetrically with respect to the line passing through the middle ofthe third opening.
 7. The display device of claim 5, wherein the firstprojection includes a pair of first bumps and a pair of third bumps, thepair of first bumps is disposed asymmetrically with respect to the linepassing through the middle of the first opening, and the pair of thirdbumps is disposed symmetrically with respect to the line passing throughthe middle of the third opening.
 8. The display device of claim 2,wherein the light emission portion disposed in the curved portionincludes a first light emission portion, a second light emissionportion, and a third light emission portion, the first light emissionportion, the second light emission portion, and the third light emissionportion respectively corresponding to one of a red pixel, a green pixel,and a blue pixel, the light emission portion in the first opening is thefirst light emission portion, and the first projection also overlaps thethird light emission portion in a third opening of the pixel definitionlayer and is symmetrically disposed with respect to a line passingthrough the middle of the third opening.
 9. The display device of claim8, wherein the wiring layer includes a data line and a driving voltageline, and a space between the data line and the driving voltage line inthe first light emission portion is different from a space between thedata line and the driving voltage line in the third light emissionportion.
 10. The display device of claim 8, wherein the wiring layerincludes a data line and a driving voltage line, a space between thedata line and the driving voltage line in the first light emissionportion is the same as a space between the data line and the drivingvoltage line in the third light emission portion, and the first lightemission portion and the third light emission portion deviate from eachother with respect to a vertical axis.
 11. The display device of claim2, wherein the light emission portion disposed in the curved portionincludes a first light emission portion, a second light emissionportion, and a third light emission portion, the first light emissionportion, the second light emission portion, and the third light emissionportion respectively corresponding to one of a red pixel, a green pixel,and a blue pixel, the light emission portion in the first opening is thefirst light emission portion, the first projection also overlaps thesecond light emission portion and the third light emission portion, thefirst projection overlapping the third light emission portion in a thirdopening is symmetrically disposed with respect to a line passing throughthe middle of the third opening, and the first projection overlappingthe second light emission portion in a fourth opening is asymmetricallydisposed with respect to a line passing through the middle of the fourthopening.
 12. The display device of claim 11, wherein the firstprojection includes a pair of first bumps, a pair of second bumps and apair of third bumps, the pair of first bumps is disposed asymmetricallywith respect to the line passing through the middle of the firstopening, the pair of second bumps is disposed asymmetrically withrespect to the line passing through the middle of the fourth opening,and the pair of third bumps is disposed symmetrically with respect tothe line passing through the middle of the third opening.
 13. Thedisplay device of claim 2, wherein the insulating layer is in contactwith an upper surface of the wiring layer.
 14. The display device ofclaim 1, wherein the thickness of the insulating layer is 15,000angstroms or less.
 15. The display device of claim 1, wherein the firstprojection is disposed closer to a first side of the first opening thana second side of the first opening, the second side being opposite thefirst side.
 16. The display device of claim 1, wherein the firstprojection includes a pair of first bumps disposed asymmetrically withrespect to the line passing through the middle of the first opening. 17.The display device of claim 1, wherein the second projection includes apair of second bumps disposed symmetrically with respect to the linepassing through the middle of the second opening.